The Kardashian sisters got their start as reality TV stars, but their star just kept on rising. Among their most recent accomplishments are a best-selling book, an array of endorsement deals and a new clothing line.

It starts early, at 8 a.m., when they hop on to onto their private jet.

They're headed for San Francisco, Calif., for an exclusive look at their very first clothing line -- Kardashian Kollection.

The short flight is just long enough for a meeting with business partner Bruno Schiavi plus a quick bite to eat before landing. For the girls, this never gets old.

They get the first glimpse of their collection inside a pop-up store at retail giant Sears, where the presale of the collection starts today.

Thanks to their mother and manager, Kris Jenner, the girls inked a deal with Sears to place their own mini-boutiques inside all 400 locations.

"We helped design this store, we picked out what we wanted from the color scheme to the carpet, so it will be cool to see," Kim Kardashian said.

TV, Fashion and Fragrance

John Goodman, the executive vice president of apparel and home for Sears, talked about the partnership.

"When you think of Sears you think of appliances, you think of tools. And how do you get people's perception to change around clothing and apparel? And that's where the girls are going to do an amazing job ... bringing in a new audience," he said.

Their growing interests have made them a triple threat: out to conquer the worlds of fashion, fragrances and, of course, reality TV.

Kim is releasing Love by Kim Kardashian. It's a soft, feminine fragrance that she will wear on her wedding day, August 20, when she walks down the aisle with basketball star Kris Humphries. There were only 1,000 bottles produced -- one for Kim, 200 for her bridal shower, and 799 for fans. The scent retails for $100 a bottle.

But just what is it about the Kardashian family that makes it such a powerful force?

Kourtney says she and her sisters are a brand to their fans.

"You get that glitz and that glamour that people want to kind of escape into. But then once they dive into us, they see that we are just like everyone else. We are so normal. We argue. We -- you know?" Kim said.

"I think we make people feel good -- about their families, because we're so weird and crazy and nuts," Khloe said. "That I'm sure we make people feel normal and like, 'Oh, thank God, I'm not like that. But it's really fun to watch.'"

Now in its sixth season, their hit show "Keeping Up With the Kardashians" has broken E! Network ratings records. The Kardashians' three spinoff shows -- "Kourtney and Khloe Take Miami," "Kourtney and Kim Take New York" and "Khloe & Lamar" -- are huge hits, too.

And the sisters, who have more than 15 million followers combined on Twitter, are not afraid to bare it all, even with all eyes on them.

Kim has been filmed undergoing an X-ray of her bottom -- to prove it's all natural. Bikini waxes aren't off limits, either.

Family Is Number 1

"The bikini waxing, after we go there you can't turn back," Khloe said.

The sisters may be light-hearted about their on-screen exploits, but when it comes to building and protecting the Kardashian brand, they are all business.

Last month, Kim sued Old Navy over a commercial featuring a look-alike of her. Old Navy's parent company, The Gap, hasn't commented on the lawsuit.

"I think that when there's confusion out there and people might mistake me for working for another company ... it was just, I think, a smart business decision to make sure that no one confuses me with anyone else other than ... my own clothing lines," Kim said.

Asked what her late father -- noted attorney Robert Kardashian -- would have thought of his daughters' success, Kourtney said: "I think he would be so proud, because he was such a strong businessman, so I think that he would love all of our business sense and, that we got from him."

Kim added that he would also be proud "that we work really hard and that, you know, we've still kept family as our number one priority."

That family keeps on growing.

The latest "K" to join the family is New Jersey Nets star Kris Humphries. He gave Kim a blinding, $2 million, 20 ½ carat diamond engagement ring. The two are set to wed on Aug. 20, and the wedding will be broadcast on E! as a special.

Kim, who describes herself as "truly a workaholic," has been balancing wedding preparations with her work.

The Kardashian sisters say they are not the party girls they once were.

They are now wives, mothers and brides-to-be, but above all, businesswomen building an incredible empire.